[PATCH evdev 0/5] Preliminary support of multitouch

Benjamin Tissoires tissoire at cena.fr
Sun Mar 28 04:58:08 PDT 2010

Hello everybody,

I started the development of multitouch in the evdev driver. As the goal of the evdev driver is to provide raw information from the kernel, I did not included any gestures nor filtering.

Currently, I have the following limitations:
- the number of simultaneous reported touchpoints is limited to 5 (arbitrary choice) in order to stay under the limit of 36 valuators

- the implementation only works for fullscreen apps (as Peter requested), i.e. I send all the mt-events in one event.

- As the current implementation of XInput in the server does not provide masking of valuators, in still send the tracking ID for each collection of touches

- I assume the tracking is made in the kernel (there are some discussion in the lkml about that)

- I also assume the device reports all the fields in each frame. I do not use the old values. So it is maybe a pitfall, but with the device I get, it's not a problem.

Apart these limitations, these patches are, I think, ready for testing.
I also pushed them on my personal xorg account[1], into the branch multitouch-unstable.


[1] git://anongit.freedesktop.org/~tissoire/xf86-input-evdev

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